1. Field of the Invention
The present invention relates to fully grouted cable bolts, in particular, a cable bolt which is adapted to receive grout through the cable and be anchored in a mine roof borehole.
2. Description of Related Art
Cable bolts are used in the mining industry for their ease of handling and installation. Cable bolts are substantially easier to fit into a borehole than the elongated rods of conventional rod bolt systems. Regardless of the height limitations in a mine, cable bolts may be adapted to boreholes of any length due to their flexibility. The strength capacity of cables exceeds that of conventional rod bolts and, therefore, cable is the preferred reinforcement for certain roof conditions.
Cable bolts are typically installed by placing a resin cartridge including catalyst and adhesive material into the blind end of a borehole, inserting the cable bolt into the borehole so that the upper end of the cable bolt rips open the resin cartridge and the resin flows in the annulus between the borehole and the cable bolt, rotating the cable bolt to mix the resin catalyst and adhesive, and allowing the resin to set about the cable bolt. In such cable bolts, the resin is typically set at an upper portion of the cable bolt at the blind end of the borehole.
In certain installations of mine roof bolts, it may be desirable to fully grout the entire length of the bolt that is received within the borehole so as to provide extended corrosion protection and/or enhanced anchorage in the surrounding rock strata.